arch/mips/kernel/irq-rm9000.c

   1 /*
   2  * Copyright (C) 2003 Ralf Baechle
   3  *
   4  * This program is free software; you can redistribute  it and/or modify it
   5  * under  the terms of  the GNU General  Public License as published by the
   6  * Free Software Foundation;  either version 2 of the  License, or (at your
   7  * option) any later version.
   8  *
   9  * Handler for RM9000 extended interrupts.  These are a non-standard
  10  * feature so we handle them separately from standard interrupts.
  11  */
  12 #include <linux/init.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16
  17 #include <asm/irq_cpu.h>
  18 #include <asm/mipsregs.h>
  19 #include <asm/system.h>
  20
  21 static inline void unmask_rm9k_irq(unsigned int irq)
  22 {
  23         set_c0_intcontrol(0x1000 << (irq - RM9K_CPU_IRQ_BASE));
  24 }
  25
  26 static inline void mask_rm9k_irq(unsigned int irq)
  27 {
  28         clear_c0_intcontrol(0x1000 << (irq - RM9K_CPU_IRQ_BASE));
  29 }
  30
  31 static inline void rm9k_cpu_irq_enable(unsigned int irq)
  32 {
  33         unsigned long flags;
  34
  35         local_irq_save(flags);
  36         unmask_rm9k_irq(irq);
  37         local_irq_restore(flags);
  38 }
  39
  40 /*
  41  * Performance counter interrupts are global on all processors.
  42  */
  43 static void local_rm9k_perfcounter_irq_startup(void *args)
  44 {
  45         unsigned int irq = (unsigned int) args;
  46
  47         rm9k_cpu_irq_enable(irq);
  48 }
  49
  50 static unsigned int rm9k_perfcounter_irq_startup(unsigned int irq)
  51 {
  52         on_each_cpu(local_rm9k_perfcounter_irq_startup, (void *) irq, 1);
  53
  54         return 0;
  55 }
  56
  57 static void local_rm9k_perfcounter_irq_shutdown(void *args)
  58 {
  59         unsigned int irq = (unsigned int) args;
  60         unsigned long flags;
  61
  62         local_irq_save(flags);
  63         mask_rm9k_irq(irq);
  64         local_irq_restore(flags);
  65 }
  66
  67 static void rm9k_perfcounter_irq_shutdown(unsigned int irq)
  68 {
  69         on_each_cpu(local_rm9k_perfcounter_irq_shutdown, (void *) irq, 1);
  70 }
  71
  72 static struct irq_chip rm9k_irq_controller = {
  73         .name = "RM9000",
  74         .ack = mask_rm9k_irq,
  75         .mask = mask_rm9k_irq,
  76         .mask_ack = mask_rm9k_irq,
  77         .unmask = unmask_rm9k_irq,
  78         .eoi    = unmask_rm9k_irq
  79 };
  80
  81 static struct irq_chip rm9k_perfcounter_irq = {
  82         .name = "RM9000",
  83         .startup = rm9k_perfcounter_irq_startup,
  84         .shutdown = rm9k_perfcounter_irq_shutdown,
  85         .ack = mask_rm9k_irq,
  86         .mask = mask_rm9k_irq,
  87         .mask_ack = mask_rm9k_irq,
  88         .unmask = unmask_rm9k_irq,
  89 };
  90
  91 unsigned int rm9000_perfcount_irq;
  92
  93 EXPORT_SYMBOL(rm9000_perfcount_irq);
  94
  95 void __init rm9k_cpu_irq_init(void)
  96 {
  97         int base = RM9K_CPU_IRQ_BASE;
  98         int i;
  99
 100         clear_c0_intcontrol(0x0000f000);                /* Mask all */
 101
 102         for (i = base; i < base + 4; i++)
 103                 set_irq_chip_and_handler(i, &rm9k_irq_controller,
 104                                          handle_level_irq);
 105
 106         rm9000_perfcount_irq = base + 1;
 107         set_irq_chip_and_handler(rm9000_perfcount_irq, &rm9k_perfcounter_irq,
 108                                  handle_percpu_irq);
 109 }